JP2817538B2 - Feedback control device and control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device and a control method for controlling a control target such as an inverter and a converter.

[0002]

2. Description of the Related Art FIG. 1 shows a feedback control device in a system for supplying power from a variable voltage source 2 comprising a PWM converter or the like to a load 1 comprising a reactor having an inductance value L. The system is configured to supply the load current I corresponding to the digital command current value I _r generated from the digital command value (reference value or target value) generator 3 to the load 1 from the variable voltage source 2. The load current I is a control amount in the feedback control system, and is detected by a current detector (control amount detector) 4 and an ADC (analog-digital converter) 5 connected thereto. AD
C5 samples the analog detection current detected by the current detector 4 at a constant sampling cycle, converts the sample into a digital signal, and outputs the digital signal. Here ADC
Let I denote both the input and output of 5 by I. Digital subtractor 6 forms the output of the difference between the detected values I and the command value I _r (error output). The digital controller 7 connected to the subtractor 6 is a control element in the feedback control system, and is composed of a microcomputer (microcomputer or microprocessor), and has a variable voltage so as to make the error signal given from the digital subtractor 6 zero. A digital manipulated variable V for operating the source 2 is formed. Note that the command value generator 3, the ADC 5, and the subtractor 6 can be included in the microcomputer together with the digital controller 7. Between the digital controller 7 and the variable voltage source 2, there is connected a hold circuit 8 which forms an analog manipulated variable corresponding to the digital manipulated variable V, holds it for one sample period, and outputs it. The hold circuit 8 includes a DAC (digital-to-analog converter) and forms an analog manipulated variable corresponding to the digital manipulated variable V. Therefore, the hold circuit 8 can also be called an analog manipulated variable generator. Here, both the digital operation amount and the analog operation amount are indicated by V. The variable voltage source 2 includes a circuit that generates, for example, a PWM control pulse in response to the analog manipulated variable V and a switching element that responds to the PWM control pulse, performs an operation corresponding to the analog manipulated variable V, and obtains an output current I. Output voltage for Here,
In FIG. 1, the hold circuit 8, the variable voltage source 2, and the load 1 are collectively called a control target. However, load 1
Only the control target may be called a control target, and the digital controller 7, the hold circuit 8, and the variable voltage source 2 may be collectively called a control element. In this case, the output voltage kV (where k is a constant) of the variable voltage source 2 becomes the manipulated variable.

[0003] When the load shown in FIG. 1 is replaced with an inductance L and a resistor R, the same control system as that shown in FIG. 1 can be formed.

FIG. 2 is a partial modification of FIG. The In 2 load 1a becomes capacitor C, where the supply current from the variable current source 2a, and is configured so as to follow the load voltage V _a to the command value V _r of the command value generator 3. The ADC 5, the subtractor 6, the digital controller 7, and the hold circuit 8 in FIG. 2 are substantially the same as those shown in FIG.

When the transfer function for the controlled object is obtained with reference to FIG. 1 using the operation amount as input and the control amount as output, the following equation (1) is obtained. GA (s) = 1 / L ^s (1) Also, the transfer function of FIG. GB (s) = 1 / C ^s (2) From Equations (1) and (2), in both FIGS. 1 and 2, the controlled object is simulated by an integral element (an element in which the output of the initial response increases with time). Both the operation amount and the control amount are similar circuits except that the voltage and the current are switched. Therefore, only the case of FIG. 1 will be described below.

[0006] Figure 3 is a control amount (load current) I and the detection value thereof is detected for each Ts in the case of the control interval are both T ^s sampling period (interval) and the controller 7 in the control device of FIG. 1 The relationship between the digital or analog manipulated variable V is shown. Note that n-2, n-1, n, and n + 1 indicate sampling points, and I ^(n-2) , I ^(n-1) , I ⁽ⁿ⁾ , I
^{(n + 1)} indicates a control amount (sample) detection value at each sampling point, and V ^(n-2) , V ^(n-1) , V ⁽ⁿ⁾ , and V ^{(n + 1)} indicate the value of each sampling interval. Indicates the amount of operation. Sampling time n
Is the current time, the manipulated variable V output at the current time n
⁽ⁿ⁾ is determined based on the control amount detection value I ^(n-1) at the immediately preceding sampling time point n-1. Therefore, control delay of one sampling time interval T ^s in a feedback control system including a digital controller 7, and the control error.

The problems related to the control delay and the control error are problems peculiar to the control system constituted by the digital controller, and it is known to use a control amount predictor as shown in FIG. FIG. 4 is a block diagram in which a control amount predictor 9 is added to the control system of FIG. In Figure 1, the hold circuits
The transfer function of the 3 8 can be expressed by the following equation (3). G _H (s) = (1−e− ^{s · Ts} ) / s (3) The variable voltage source 2 can be represented by a proportional element k. Further, since the transfer function of the controlled load 1 is represented by the equation (1), the total transfer function G (s) from the hold circuit 8 to the controlled load 1 is represented by the following equation (4). _{G (s) = G H (} s) · k · G A (s) = ((1-e -s · Ts) / s) · k · (1 / Ls) = k · (1-e -s · ^{ts) / (s 2 L)} (4) where, expressed G (s) is the discrete time domain by Z conversion by formula Z transform becomes the following expression (5). G (z) = (k · Ts / L) · (1 / (Z−1)) · Z ⁻¹ (5) In FIG. 4, 7 is a digital controller represented in a discrete time domain, and 10 is an equation ( 5) a transfer function from the hold circuit 8 to the controlled load 1 represented by 5), 11 is a one-sample delay element, 9 is a control amount predictor, 12 is an adder, 6 is a subtractor,
3 is a command value for the control amount. The line 13 corresponds to the output of the ADC 5 in FIG. 1, and the control amount detection value is obtained here. One input terminal of the adder 12 is connected to the line 13, and the other input terminal is connected to the predictor 9. The predictor 9 is connected to the digital controller 7 via the delay element 11 and calculates a predicted value Δi (n−1) based on the digital manipulated variable V.
Occurs.

More specifically, the predictor 9 has
Increase in control amount when the operation amount V is given to the control targetAdditionMinute (odd
) Is calculated and predicted. Therefore, the control target in this example is
Since the reactor 4 is used, the function for calculating the increase is (k / Ln
 ) · Ts (where Ln represents the nominal value of L)
Let In the case of FIG. 2, it becomes (k / Cn) .Ts.
Where Cn is the nominal value of C. FIG. 5 shows a state of the control.
At time (n-1), the control amount I (n-1) is
To detect. Further, the manipulated variable v (n) output at the time (n-1)
-1) is obtained by the delay element 11 and input to the predictor 9.
And increase the control amount in Ts timeAdditionThe minute predicted value Δi (n-1) is
Desired. This control amount increase predicted value and the detected control
Control amount prediction at the time point n by adding the amount by the adder 12
The value i (n) is obtained. The control amount prediction at the obtained n time point
The control error is obtained from the value and the command value by the subtractor 6, and the
The digital controller 7 controls the control error to converge to zero.
MV output during one sample period from the time point nV
(N) is determined and output to the control object during the period from n to n + 1.
You. Control error caused by one sample time by this method
Is compensated. However, a constant (for example, L) to be controlled is
If it does, an error will occur. The error is long prediction time
It is big. Here, the variation of the constant of the controlled object is represented in FIG.
In the example, the inductance value L fluctuates,
Load 1 has resistance along with inductance L
And so on.

[0009] An object of the present invention is to control an object to be controlled by disturbance or the like.
Control performance deterioration due to constant fluctuations can be suppressed.
And a feedback control apparatus and method .

In order to achieve the above object, the present invention provides a digital control variable which detects a control variable of a control target or a variable corresponding thereto at a predetermined sampling time interval to obtain a digital variable control variable detection value. and detecting means, and the digital command value generating means for the control amount detection value is generated by a digital quantity command value to be followed, subtracting means, di di Tal
A controller, first and second adding means, a delay element, a control amount change predicting means, and a prediction error detecting and compensating means, wherein the first adding means is a control amount detecting means; detection
Output of the control amount change predicting means to the detected control amount detection value.
The is intended to create an addition to controlling the amount predicted value, as the subtraction means for generating an output corresponding to the difference between the command value and resulting et a said control amount predicted value from said first addition means Wherein the digital controller outputs an operation amount for controlling the control target based on an output obtained from the subtraction means, and the delay element includes the digital
A predetermined sampling is performed on the manipulated variable obtained from the
Outputs a delayed signal with a time interval delay.
The second adding means adds the prediction error to the delayed signal.
Add the prediction error compensation amount obtained from the detection and compensation means
A shall, said control amount variation estimating means, said second
Outputs and control of groups Zui by the current sampling time in the constant of the control target of the adding means and the next sampling
The predicted value of the change from the point control amount is calculated by calculation .
The prediction error detecting and compensating means obtains a prediction error based on a difference between the control amount predicted value and an actual control amount detected value, and compensates the prediction error to converge to zero. Amount, and calculate the prediction error compensation amount as described above.
The present invention relates to a digital feedback control device which is sent to a second adding means . It should be noted that the prediction error compensation value can be added to the output of the control amount change predicting means as described in claim 2. Claim 1
The methods of claims 3 and 4 can be adopted corresponding to the devices of the first and second aspects.

[0011]

[Operation and Effect] In the present invention, the control amount predicted value and the actual
The prediction error consisting of the difference from the control amount detection value at
Prediction error compensation by compensating the prediction error to converge to 0
The quantity is determined and used for the control quantity prediction. This allows
Even if the constant of the controlled object fluctuates due to disturbance, etc., this was taken into account.
Control amount prediction value can be determined, improving control performance
Can be made.

[0012]

First Embodiment Next, a feedback control device according to a first embodiment of the present invention will be described with reference to FIGS. However, in FIGS. 6 and 7, portions common to FIGS. 1 to 5 are denoted by the same reference numerals, and description thereof is omitted. As is clear from the comparison between FIG. 6 and FIG. 4, the method of FIG. 6 is different from the method of FIG. 4 in that a prediction error detector 14, a prediction error compensator 15,
An adder 16 is added. That is, this compensation means is provided in addition to the control amount change prediction means 9b . The newly provided adder 16 outputs the output V (n−n−
1) and the prediction error compensation amount obtained from the prediction error compensator 15 are added and sent to the change (increase) predictor 9b. The prediction error detector 14 includes a delay element 17 for one sample period and e
It comprises a circuit 18 of xp (−mTs) and a subtractor 19.
The delay element 17 is connected to the output line of the adder 12, and (n) is one sample period Ts before the control amount prediction value i (n).
The control amount prediction value i (n-1) in (-1) is output.
The circuit 18 detects the control amount detection value I (n-1) at the time of (n-1).
Is output. Therefore, the predicted value i (n) is output from the subtractor 19.
−1) and the output Δie (n−) of the difference between the detected value I (n−1).
1) is obtained as a prediction error. The prediction error compensator 15 includes a circuit of kz / (z−1), and sends a prediction error compensation amount to the adder 16. In FIG. 6, the control amount predictor 9a, the prediction error detector 14, the prediction error compensator 15, and the adders 12 and 16 are functionally shown as blocks.
(Digital signal processor) or microcomputer,
It is processed by software according to a predetermined program.

[0013] In this embodiment, as shown in FIG. 7, the m points during each sampling time interval T _s is provided, detection of the control amount, and the timing of the output of the manipulated variable is as follows. The description will be made by taking an example between the points (n-1) and (n).
from n-1 to detect the m points until n words (n-1, m) T _s point of controlled variable I _{(n-1, m)} is output at n points. Here, m takes a value between 0 and 1. When m = 1, there is no control delay. When m = 0, a control delay of one sample occurs. Therefore, the predicted time is (1−m) T _s
It becomes less than one sample time.

Next, the transfer function in the discrete time domain of the controlled object at the above timing can be expressed by equation (6) by extended Z-transform. G _(z , _m) = (k · T _s / L) · (m _(Z−1) +1) / (Z−1)) · Z−1 (6) Further, the control amount is increased by the predictor 9b. The function to find is (1
-M) To predict after T _s time: (K / L _n ) · (1-m) T _s

By introducing the timing m, FIG.
Is controlled by (kT _s / L) ｛[m _(z−1) +1] /
A control amount detection value indicated by I _{(n-1, m)} is obtained as an output from the block 10a indicated by (z-1)} and the delay element 10b of one sample. Further, the predictor 9b calculates (k /
L _n ) (1-m) T _s , and the predicted value Δi _(n− ) of (1-m) T _s time control amount increase from (n−1, m) T _s to (n) T _{s 1, m)} is output.

In FIG. 6 and FIG. 7, (n-1) T s during the operation amount is output to the controlled object v _(n-1) and (n-1) T _s
The value obtained by adding the output value of the prediction error compensator 15 at the time by the adder 16 is input to the predictor 9b to calculate the control amount increase predicted value Δi _{(n−1, m)} after (1−m) T _s. I do. Also, (n-1,
m) The control amount I _{(n-1, m)} at the time of T _s is detected, and the value is Δi
By adding _{(n-1, m)} by the adder 12, (n) T _s
The control amount prediction value i _{(n) at the time} is calculated. Also, (n-1)
Predicted control variable i _(n-1) and (n-1, m) at T _s
Difference T mT _s time delay elements of the control amount detection value at the time _s, i.e. the (n-1) T _s during the control amount detection value I _(n-1) Δi
_{e (n-1)} is the prediction error of the control amount at the time (n-1) T _s. In order to converge the prediction error to 0, the prediction error is input to the prediction error compensator 15 composed of an integral element, and the output, which is the prediction error compensation amount, is input to the operation amount V, which is the input value of the predictor 9b. By adding to _(n-1) , the control value increase predicted value is compensated. The (n) T _s during the control amount predicted value i _(n) and compares the command value I _{r (n)} to obtain a control error, the digital controller 7 based on the error converges to the error is 0 Such an operation amount v _(n) is determined, and (n) T _s
Sometimes output.

[0017] If the above operation is constant L of the controlled load 1 in Figure 1 has changed from the nominal value L _n, load 1 follow precisely the command value I _r even when including a resistive component R with L Control performed is realized.

[0018]

Second Embodiment Next, a feedback control device according to a second embodiment of the present invention will be described with reference to FIG. However, in FIG. 8, portions common to FIG. 6 are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, the output of the prediction error compensator 15 is added to the output of the predictor 9b using the adder 12. Others are the same as those in FIG. 6, and thus the same operation and effect can be obtained.

[0019]

Third Embodiment FIG. 9 shows an example in which the present invention is applied to a PWM converter. This PWM converter device has 3
It has a PWM converter circuit 23 connected to the phase AC power supply 20 via a capacitor 21 and a reactor 22.
The converter circuit 23 is a three-phase bridge circuit of six switching elements Q composed of IGBTs. A smoothing capacitor 24 is connected to this output line, and a load 25 is further connected. The switching element Q is turned on / off by a known control signal supplied from the pulse width conversion circuit 26, and converts a three-phase alternating current into a direct current to output. In this embodiment, the reactor 22, the conversion circuit 23, the capacitor 2
4, the load 25 and the pulse width conversion circuit 26 can be regarded as a control target 37 together. The control target 37 corresponds to the control target 10 in FIG. In order to detect a control amount from the control target 37, two current detectors 27 and an ADC (A
/ D converter) 28, and the ADC 28 is connected to the control amount predictor and the compensator 29. The control amount estimator / compensator 29 includes the prediction means 9a and the prediction error detector 1 shown in FIG.
4 and the prediction error compensator 15, and outputs control prediction values i _u and i _w for two phases. These i _u and i _w are shown in FIG.
I _(n) .

A digital reference sine wave generator 30 is provided corresponding to the command value generator 3 shown in FIG.
It comprises a ROM in which sine wave data is stored, and generates a current phase reference signal for two phases consisting of digital sine wave data in synchronization with the sine wave voltage of the power supply 20. The device shown in FIG. 9 is configured to perform on / off control of the switching element Q so that the input current of the converter circuit 23 approaches a sine wave. A multiplier 31 for two phases is provided to execute both the control for making the current waveform close to a sine wave and the control for making the output voltage constant, and a reference sine wave is provided at one input terminal. Generator 30 is connected,
A voltage control system is connected to the other input terminal. The voltage control system includes an ADC 32 for detecting an output voltage and an error amplifier 3
3 and a PI circuit 34. Note that, in order to facilitate the description, the operation by the voltage control system will be omitted. The two-phase output signal of the multiplier 31 is the current command value signal in FIG. 6, and is represented by iu * and iw *, respectively. Further, the subtracters 35 for the two phases in the output stage correspond to the subtractor 6 in FIG. 6, and the control predicted values i _u and i _w and the command value iu * given from the control amount predictor and the compensator 29. , Iw *. This error signal is output to the PI circuit 3 for two phases.
6 to be manipulated variables V _u , V _w , which are sent to the pulse width conversion circuit 26. The manipulated variables V _u and V _w correspond to V _(n) of the output of the controller 7 in FIG. Subtractor 38 is to form the remaining one phase of the operation amount V _v based two phases of the operation amount V _u, the V _w.

The amount of operation required by the control amount predictor and compensator 29 is obtained from the output of the PI circuit 36. Note that FIG.
The region surrounded by the chain line 39 is constituted by a DSP or a microcomputer. Manipulated variable V _u, V _v, V _w are used as the pulse width data, the switch control signal consisting of an analog of the operation amount in the pulse width conversion circuit 26 S _u, S _v, is converted to S _w. The pulse width conversion circuit 26 corresponds to the hold circuit 8 in FIG. Also, the converter circuit 23 is shown in FIG.
The reactor 22 corresponds to the load 1 in FIG. The clock generator 40 generates a timing clock for determining a sampling interval and an arithmetic control interval, which becomes an interrupt signal of the DSP. The interrupt signal starts and executes a program for detecting a control amount and performing arithmetic processing.

The operation of this device is represented by D
The software is realized by the SP. FIG. 10 shows a flowchart for only the portion of the software relating to the present invention. A through H in the figure are working registers. The values of the registers are also indicated by A to H.
k, L _n , m, and T _s are constants. V _u , V _w , I _u ,
I _w , i _u , i _w , Δi _u , Δ i _w , i _u *, i _w * are variables. D _(z) is a function. The flowchart will be described below.

Initial settings are made in the first step 50 after the start. This initialization is a reset of working registers and variables. Next, at step 51, the process waits for an interrupt. Next the operation amount V _u that is calculated in the previous processing in step 52, and outputs a V _w. Next, at step 53, the control amounts I _u and I _w are read from the ADC. Next, in step 54, the control amount prediction values i _u , i _w calculated in the previous process are subtracted from the control amount read from the ADC 28 and stored in the registers A, B. That is, the control amount prediction error detection value is stored in the registers A and B. Next, at step 55, the values of the registers A and B are multiplied by the constant k and the values of the registers C and D are added, and the result is stored in the registers C and D again. Thus, the prediction error compensation amounts are stored in the registers C and D.
Next, in step 56, and stores the operation amount V _u output in step 52, registers V _w C, prediction error compensation amount C of D, D was added register E, the F. Next, as shown in step 57, the values obtained by multiplying the values of the registers E and F by the constant K, further multiplying by (1−m) T _s and dividing by L _n are used as the control amount increase predicted values Δi _u and Δi _w. Store. Next, as shown in step 58, the control amounts I _u and I _w are
Read from. Next, as shown in step 59, AD
The control amount increase predicted values Δi _u , Δi _w are added to the control amounts I _u , I _w read from C28 to obtain control amount predicted values i _u , i _w and stored in registers. Next, as shown in step 60, the predicted control values i _u , i _w are subtracted from the command values i _u *, i _w * (output of the multiplier 35) and stored in the registers G, H. Next, as shown in step 61,
From the values of the registers G and H and the function D (z), an operation amount V _u ,
Find V _w and store it in a register. Thereafter, the process returns to step 51. Here, from step 51 to step 5
8 is the time until the start become mT _s time. The program is activated and executed by interruption at T _s time interval.

From the above, if there is no sudden change in the constant of the control target between the sampling points (such as a change in L in this example), the prediction error converges to 0 with the time constant of the integral element. As a result, the approximation even when there is an error or fluctuation predict precisely controlled amount, digital control specific sampling interval of the model for the control target of the control amount prediction (modeled by L _n in this example), and control interval This makes it possible to compensate for the deterioration of control performance caused by the above. This method is a method in the case of one sample delay if m is set to 0. Therefore, it can be applied to the conventional prediction method.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a conventional feedback control device.

FIG. 2 is a block diagram showing another conventional feedback control device.

FIG. 3 is a diagram showing a relationship between a control amount and an operation amount in FIG. 1;

FIG. 4 is a block diagram showing another conventional feedback control device.

FIG. 5 is a diagram illustrating a control amount, a control amount prediction value, and an operation amount in FIG. 4;

FIG. 6 is a block diagram functionally showing the feedback control device according to the first embodiment of the present invention.

FIG. 7 is a diagram showing a control amount, a control amount prediction value, and an operation amount in FIG. 6;

FIG. 8 is a block diagram functionally showing a feedback control device according to a second embodiment of the present invention.

FIG. 9 is a block diagram showing a converter device according to a third embodiment of the present invention.

10 is a flowchart showing an operation of determining the manipulated variable in the converter device of FIG. 9;

[Explanation of symbols]

 3 Command value generator 7 Digital controller 10 Control object 9 Control amount prediction means 14 Prediction error detector 15 Prediction error compensator

Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) H02M 7/00-7/98 H02M 3/00-3/44 G05B 21/02 G05F 1/10

Claims (4)

(57) [Claims] 1. A digital control amount detecting means for detecting a control amount of a control object or a corresponding amount at a predetermined sampling time interval to obtain a control amount detection value of a digital amount; Digital command value generation means for generating a command value to be followed by a digital quantity , and subtraction
Means, a digital controller, and first and second adding means
, A delay element, a control amount change amount predicting unit, and a prediction error detecting and compensating unit, wherein the first adding unit is detected by the control amount detecting unit.
Add the output of the control amount change predicting means to the control amount detection value
A predicted value of the control amount, and the subtraction means outputs the control value obtained from the first addition means.
Generates an output corresponding to the difference between the control value predicted value and the command value.
Shall, as described above, and said digital controller obtained from said subtraction means output
Outputs the manipulated variable for controlling the control target based on
Is intended to, the delay element is obtained from said digital controller wherein
A delay that gives a delay of the specified sampling time interval to the manipulated variable
And outputs a rolling signal, the second addition means the prediction error detection to the delay signal
And the prediction error compensation amount obtained from the compensation means
And the control amount change predicting means outputs the output of the second adding means.
Current sampling based on the force and the constant of the controlled object.
Between the control amount at the sampling time and the control amount at the next sampling time
The prediction value of the change is calculated by calculation , and the prediction error detection and compensation means includes the control amount prediction value and
The prediction error is calculated based on the difference from the actual control amount detection value.
Is compensated so that the prediction error of
A difference compensation amount is obtained, and the prediction error compensation amount is added to the second addition.
A digital feedback control device for sending to a means . 2. A digital control amount detecting means for detecting a control amount of a control target or a corresponding amount at a predetermined sampling time interval to obtain a control amount detection value of a digital amount, and said control amount detection value. Digital command value generation means for generating a command value to be followed by a digital quantity , and subtraction
Means, digital controller, summing means, delay element
Control amount change predicting means, and prediction error detection and compensation means.
Possess a stage, said addition means control amount detected by the control amount detection means
The detected value, the output of the control amount change amount predicting means, and the prediction error
Add the output of the difference detection and compensation means to obtain the control amount prediction value.
The subtraction means calculates the control amount forecast obtained from the addition means.
Generating an output corresponding to the difference between the measured value and the command value
And the digital controller outputs the output obtained from the subtraction means.
Outputs the manipulated variable for controlling the control target based on
The delay element is added to the manipulated variable for a predetermined sampling time.
Outputting a delay signal with a delay of an interval, wherein the control amount change predicting means includes the delay signal and the control signal.
Control of the current sampling point based on the constant of interest
Of the change between the control amount and the control amount at the next sampling time
The measurement value is calculated by calculation, and the prediction error detection and compensation means includes the control amount prediction value and
The prediction error is calculated based on the difference from the actual control amount detection value.
Is compensated so that the prediction error of
The difference compensation amount is obtained, and this prediction error compensation amount is sent to the adding means.
Digital feedback control device characterized by sending
Place. 3. A digital control amount detecting means for detecting a control amount of a control target or a corresponding amount at a predetermined sampling time interval to obtain a control amount detection value of a digital amount; A digital command value generating means for generating a command value to be followed by a digital quantity, and a predetermined control time interval for an operation amount for obtaining a control amount detection value corresponding to the command value from the digital control amount detecting means. before SL control pair was determined by digital operation in
Digital control means for controlling an elephant
A method of controlling the controlled object by a feedback control device.
Therefore, the digital control means determines the operation amount.
, A subtraction step, a digital control step, and a first
And a second adding step, and a delay step, the control amount change
Compound prediction step and step of calculating prediction error compensation amount
And in the first adding step, the control amount detecting means
The control amount change amount prediction value is added to the control amount detection value detected in
The control amount prediction is performed by adding the control amount change prediction value obtained in step.
A measurement value, and in the subtraction step, in the first addition step
The difference between the created control amount predicted value and the command value
Output in the digital control step.
Control the control target based on the output created in the
In the delaying step, the operation amount is determined by a predetermined sample.
A delay signal delayed by a ring time interval is created, and in the second adding step, the delay signal is added to the delay signal.
A value obtained by adding the prediction error compensation amount is created, and in the control amount change amount prediction step, the second addition is performed.
Between the added value created in the calculation step and the constant to be controlled
Based on the control amount at the current sampling time and the next
By calculating the predicted value of the change from the control amount at the time of pulling
Calculating and calculating the prediction error compensation amount,
The prediction error is determined by the difference between the control amount prediction value and the control amount detection value.
And compensated to make this prediction error converge to 0.
A feedback control method, wherein the prediction error compensation amount is created . 4. A control amount of a control object or a control amount corresponding to the control amount.
At a predetermined sampling time interval.
Digital control variable detection to obtain digital variable control variable detection value
Output means and a command value to be followed by the control amount detection value in digital quantity.
The digital command value generating means and the digital control amount detecting means correspond to the command value.
The operation amount for obtaining the control amount detection value
The control pair is determined by digital operation at
Digital control means for controlling an elephant
In the method of controlling the control target by a feedback control device,
The digital control means determines the manipulated variable.
In the subtraction step, and Dialog Ijitaru control step, adding
Step, delay step, and control amount change prediction step.
And a step of calculating a prediction error compensation amount. In the adding step, the control amount detection unit detects
And the control amount change amount predicting step.
The control value change amount prediction value obtained in the above and the prediction error compensation amount
Adding to create a controlled amount prediction value, in the subtraction step, created in the adding step
Output corresponding to the difference between the control value predicted value and the command value.
Create and in the Tijitaru control step, the subtraction step
Control the control target based on the output created in the
In the delaying step, the operation amount is determined by a predetermined sample.
A delay signal delayed by a ring time interval is created, and in the control amount change estimation step, the delay signal
Current sampling based on the
Change between the control amount at the time and the control amount at the next sampling time
Calculating the predicted value of the compound by calculation and obtaining the predicted error compensation amount,
The prediction error is determined by the difference between the control amount prediction value and the control amount detection value.
And compensated to make this prediction error converge to 0.
A feedback control method, wherein the prediction error compensation amount is created .